Trialkyl-1-benzoylpropane-1,2,3-tricarboxylates and process of preparing same



Patented Jan. 26, 1954 2,667,504

UNITED STATES @ATENT OFFICE TRIALKYL 1 BENZOYLPROPANE 1,2,3 TRICARBOXYLATES AND PROCESS OF PREPARING SAME Joachim'Dazzi, Dayton, Ohio, assignor to Monsanto ChemicalCompany, St. Louis, Mo., a corporation of Delaware No Drawing. Application May 24,1951, Serial No. 228,111

Claims. (Cl. 260 -475) i 2 v The present invention relates to organic comeither reactant is decomposed. Refluxing tempounds and deals more particularly with addiperatures of the reaction mixture are preferred. tion products of dialkyl fumarates and certain Termination of the reaction is generally eviketo-esters, to methods of preparing the same, denced by noting cessation in rise of the refluxand to vinyl chloride polyymers plasticized with 5 ing temperature. The course of the reaction the addition products. 1 may also be followed by noting the change in According to the invention there are provided the refractive index of the reaction mixture. new and valuable polycarboxylates in which one Since the present products are formed by admole of a dialkyl fumarate of from 6 to 12 cardition of one mole of the fumarate to one mole bon atoms is combined with one mole of an alkyl ll) of the keto-ester, molar equivalents of the re aroylacetate in which the alkyl radical has from actants may be advantageously employed in the l to 4 carbon atoms and the aroyl radical is reaction mixture. However, since any unreacted selected from the class consisting of the benzoyl, materials may bereadily recovered from the rethe 2-toluoyl, the 3-toluoyl and the 4-toluoy1 action product, an excess of either reactant may radicals. The new polycarboxylates are formed .5- be used; and in order to assure complete reaction y a simple addition reactiomin W ch one mole of the less readily available keto-esters, it .is of the fumarate adds to one mole of the aroylgenerally preferred to use an excess of the diacetate. While the structure of the 1:1 adducts alkyl iumarate in the initial reaction mixture. thus formed cannot be definitely determined, An excess or the fumarate also serves as a the adducts are believed to be'trialkyl l-aroyl- 2O diluent for the reaction. p p carboxylates, the addition re- The present adducts are stable, high-boiling action proceeding probably according to the polycarboxylates which range from clear, viscous scheme: liquids to waxy solids. They are advantageously Y R/OOQCH used for a variety of industrial purposes, and

II are characterized by conferring improved plas- CH'COOR ticity to synthetic resins and plastics when in- Y corporated therein. 'ihey impart increased flex- 013E000}; ibility to vinyl chloride polymers, which flex- OHCOOR, ity is retained at even low temperatures. At o g a u es. e present adducts are not Q1320 readily volatilized from the plasticized composiin which Y is selected from the class consisting tion, even when present in concentrations of of hydrogen and the methyl radical and R, R up to by welght. I and R" are alkyl radicals of from 1 to 4 carbon The invention is further illustrated, but not atoms. as limited, by the following examples.

Dialkyl fumarates useful for the preparation Example 1 of the present adducts are esters in which the alcohol portions of the molecule are derived from A mlXturB 0f r-9 mole) ethyl b oy one alcohol, i. e., the diethyl, dimethyl, di-isoacetate and 207 g. (1.2 moles) of dlethyl fumarate propyl, di-n-propyl, di-n-butyl, di-tert-butyl or was refluxed for 77 hours at a temperature of diisobutyl fumarates, or mixed esters such as t0 Frafctlonatlon of ethyl methyl fumarate, propyl ethyl fumarate, resulting product gave a fract1on B P. 180-268 butyl ethyl fumarate, etc. Examples of aroylwhlqh 1 9 redlstlllatlon ave acetates useful for the present purpose are 46. g. of an addu t 1n Whl0h e mole of ethyl methyl, ethyl, isopropyl, n-propyl, 1:1-butyl i benzoylacetate is combined with one mole of dibutyl Or tert-butyl benzoylacetate, methyl 2 ethyl m e p bly hyl -benz yltoluylacetate, n-propyl 3-toluylacetate, isobutyl P D -L B- a 0 y1ate B. P. 196-2 10 4-toluylacetate, etc. 0/0.? mm., ND 1.4875 having a saponificatlon The addition reaction is effected imply by equivalent of 107.5 and 21.11 acid content Of 5.13%. heating the fumarate with the aroylacetate at a to temperature of at least 200 C. until formation Example 2 of the 1:1 adduct has occurred. The heating 60 parts of polyvinyl chloride and 40 parts by temperature may be from 200 C. to 300 C., deweight of the adduct of Example 1 were mixed pending upon the nature of the individual reacton a rolling mill to a homogenous blend. During ants; it should not exceedatemperature at which to the milling there was observed substantially no fumes and discoloration. A molded sheet of the mixture was clear transparent and substantially colorless. Testing of the molded sheet by the Clash-Berg method gave a low temperature flexibility value of 4 C. Tests on the volatility characteristics of the plasticized composition employing the method described by the American Society for Testing Materials under the designation D-74444T gave a volatility value of 2.7 per cent. When subjected to a heat of 225 F. for a period of 30 minutes the clarity and color of the molded product were substantially unchanged.

While the above example shows only compositions in which the ratio of plasticizer to polymer content is 40:60, this ratio being employed in order to get comparable efficiencies, the content of adduct to polyvinyl chloride may be widely varied, depending upon the properties d sired in the final product. For many purposes a plasticizer content of, say, from only 10 per cent to 20 per cent is preferred. The present adducts are compatible with polyvinyl chloride over wide ranges of concentrations, up to 50 per cent of esters based on the total Weight of the plasticized composition yielding desirable products.

Although the invention has been described particularly with reference to the use of the present adducts as plasticizers for polyvinyl chloride,

they are advantageously employed also as plasticizers for copolymers of vinyl chloride, for example, the copolymers of vinyl chloride with vinyl acetate, vinylidene chloride, etc. Preferably, such copolymers have a high vinyl chloride content, i. e., a vinyl chloride content of at least 70 per cent by weight of vinyl chloride and up to 30 per cent by weight of the copolymerizable monomer.

The plasticized polyvinyl halide compositions of the present invention have good thermal stability; however, for many purposes it may be advantageous to use known stabilizers in the plasticized compositions. Inasmuch as the present adducts are substantially unreactive with the commercially available heat and light stabilizers which are commonly employed with polyvinyl chloride or copolymers thereof, the presence of such materials in the plasticized materials does not impair the valuable properties of the present esters. general utility in softening vinyl chloride polymers. They may be used as the only plasticizing component in a compounded vinyl chloride polymer or they may be used in conjunction with other plasticizers.

The present adducts are of 4 What I claim is: l. A compound having the formula G-coouooos (XJELCOOR' CHzC 0 OR Gooomcoon in which Y is selected from the class consisting of hydrogen and the methyl radical and R is an alkyl radical of from 1 to 4 carbon atoms with a dialkyl fumarate in which each alkyl radical has from 1 to 4 carbon atoms, and recovering from the resulting reaction product a tricarboxylate having the formula Q-oaoaooou CH.COOR

CH2.COOR

in which Y is selected from the class consisting of hydrogen and the methyl radical and R, R and R." are alkyl radicals of from 1 to 4 carbon atoms.

7 5. The method which comprises heating, at a temperature of at least 200 C., a mixture of ethyl benzoylacetate and diethyl furnarate and recovering triethyl l-benzoylpropane-1,2,3-tricarboxylate from the resulting reaction product.

JOACHIM DAZZI.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,706,639 Van Schaak et a1. Mar. 26, 1929 2,075,107 Frazier Mar. 30, 1937 2,456,517 Ladd Dec. 14, 1948 2,472,135 Weizmann June 7, 1949 2,517,351 Reid Aug. 1, 1950 2,526,395 Nichols Oct. 17, 1950 

1. A COMPOUND HAVING THE FORMULA
 4. THE METHOD WHICH COMPRISES HEATING AT A TEMPERATURE OF AT LEAST 200* C., A KETO-ACETATE HAVING THE GENERAL FORMULA 